Abstract

The stop-signal task has been used extensively in order to test abilities of inhibition as
well as cognitive functioning. In previous experiments, a relatively large number of
participants had to be excluded from analysis because of poor performance on the task.
In this experiment, we examined the differences between adequate and poor performers
on a stop-signal task embedded in an emotional lexical decision task. The personality
and behavioral data of the poor stop-signal task performers did not differ from the
adequate performers, but the P3 and error-related negativity (ERN) ERPs provided
evidence that the poor stop-signal performers attended to the lexical decision portion of
the task rather than the stop-signal. However, poor stop-signal task performers did not
fail to process the stop signal. These results suggest that the selection of the task in which
the stop signal is embedded is crucial.